Naturally occurring uranium is composed of which combination of isotopes__________________?
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Answer: A. 99.282% U238, 0.712% U235, 0.006% U234
Explanation
Naturally occurring uranium is a mixture composed of three distinct radioactive isotope species. Uranium-238 constitutes the vast majority of natural deposits at approximately ninety-nine percent. Uranium-235 and trace amounts of uranium-234 make up the remaining small fraction of the total. Isotopes are variants of a chemical element sharing identical proton counts but differing neutron numbers. Uranium-235 is the primary fissile isotope required to sustain nuclear fission chain reactions. Radiometric dating techniques rely on the natural radioactive decay chains of these uranium isotopes.
Mining operations extract natural uranium ore containing these precise isotopic abundance percentages. Fuel fabrication facilities must process natural uranium to increase the fissile isotope concentration. Understanding isotopic composition is essential for nuclear safeguards, fuel cycle analysis, and reactor design. Inverting the primary percentages confuses the abundant U-238 with the scarce U-235 isotope. Placing major percentages on minor isotopes like U-234 violates established geological survey data. Altered decimal places in alternative options contradict well-established nuclear chemistry measurements.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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